1. Field of the Invention
This invention relates to an image processing apparatus which reads an image of an original, performs processing for the read image, and outputs a processed image.
2. Description of the Related Art
Copiers have been known in which an image of an original is read, and the read image is recorded on paper or the like. In such a conventional copier, when it is desired to obtain an output image of an image of an original having a size so large that a reading unit of the copier cannot read the image in a single reading operation, the image of the original is, for example, divided into four portions, the respective portions are read, the read images are individually recorded, and the operator connects four recorded images to provide one image.
However, this approach has the problem that the operator must paste a plurality of recorded images in order to connect them, and the operation of pasting images is troublesome.
Copiers having an editing function have also been provided in which an area is assigned for each of a plurality of images of an original, respective images of assigned areas are synthesized, and a synthesized image is output.
In such a copier, an area is assigned, for example, by inputting the numerical values of coordinates using keys on an operation unit while watching an original, or by inputting the position of coordinates by pressing a pad surface of a digitizer with a pen point. By such an operation, images other than those in assigned areas are erased from image data received in the copier, and output images are synthesized by transferring a plurality of images on a single sheet of recording paper.
In such an approach, however, a troublesome operation is needed, since areas must be manually assigned. Furthermore, a high-degree of skill is needed for performing exact positioning in order to connect a plurality of images, and a difficult operation must be performed.
Recently, needs for large-size originals, such as maps, PERT charts, CAD drawings and the like, have increased. For such needs, digital color copiers which can read large-size, such as the A1 size or the like, originals have been proposed.
However, the sizes of not a few actual large-size originals exceed the A1 size, for example, the B1 size, the A0 size and the like. It is possible to propose an image reading apparatus having a much larger original mount. Such an apparatus, however, has the disadvantages that original-mount glass is deflected by its own weight, whereby the distance between an image pick-up device and an original differs at a surrounding portion and at a central portion, adversely influencing an image and increasing installation space.
It is also possible to provide a sheet feed mechanism, which moves a scanner only in the main scanning direction, and moves an original in the sub-scanning direction, in a reader unit. In such a mechanism, the size of the original is not limited at least in the sub-scanning direction.
In an apparatus including such a reader unit, however, an original to be set must be in the form of a sheet, and a reading operation is limited by the size of an original. Furthermore, such an apparatus also has the disadvantages that in order to move an original in the above-described manner, control for obtaining accuracy is difficult, and the production cost will be increased.